WASHINGTON (Reuters) - The conservative House Freedom Caucus came out in support of a reworked U.S. healthcare overhaul bill even though it would not fully repeal Democratic former President Barack Obama's signature healthcare law, the group said in a statement on Wednesday.

The group last month helped sink an effort to pass a Republican healthcare overhaul, called the American Health Care Act. But it remained unclear whether the amended bill could win enough support from moderate Republicans to get the 216 votes needed to pass the U.S. House of Representatives given unanimous Democratic opposition.

"While the revised version still does not fully repeal Obamacare, we are prepared to support it to keep our promise to the American people to lower healthcare costs," the House Freedom Caucus said in a statement posted on the website of its chairman, Republican Representative Mark Meadows.

Republicans in Congress have made repealing and replacing the Affordable Care Act, commonly known as Obamacare, a central campaign promise for seven years. Republican President Donald Trump also made it a top campaign promise.

The Republican healthcare bill would replace Obamacare's income-based tax credit with a flat age-based credit, roll back an expansion of the Medicaid government health insurance program for the poor and repeal most Obamacare taxes. The nonpartisan Congressional Budget Office estimated 24 million fewer people would have insurance under the bill.

In its statement, the House Freedom Caucus said it welcomed an amendment that would let states seek waivers from some Obamacare requirements, including the highly popular provision mandating that insurers charge those with pre-existing conditions the same as healthy consumers and that insurers cover so-called essential health benefits, such as maternity care.

The amendment was hammered out between Meadows and Representative Tom MacArthur, a leader of the so-called Tuesday Group of Republican moderates in the House.

Yet several moderates said on Wednesday they had not yet made a decision on whether to support the bill while others remained opposed. Some complained that they had not been part of discussions drafting the amendment, saying they had only seen it after it was released.

"It doesn't address any of the concerns I've been raising for weeks," said Republican Representative Charlie Dent, including how to reform Medicaid.

Republican Representative Chris Collins, another member of the Tuesday Group, said pressure to follow through on Republicans' top campaign promise for the past seven years had shifted from the party's conservative wing to the moderates.

"We need to get this passed to fulfill our campaign promise, and this is the compromise that looks like it will make it happen," he said.

Republican leaders have not scheduled a vote on the bill. They said they would do so when they are confident they have the votes needed for passage.